90 NATURAL HISTORY OF 



Among the true Gallinaceous birds, we find tlie 

 different members living very much upon the ground, 

 ihe power of flight limited, from the great weight 

 of their bodies or unwieldiness of plumage, and very 

 commonly an extraordinary development of the parts 

 composing the tail. In the present family, the 

 ground is still their prevailing habitation, though 

 many of them frequently perch and roost on trees. 

 Their power of flight is ample, very strong, in some, 

 as the genus Pterocles, extremely rapid, but in a 

 few forms almost as little used as among the Pa- 

 vonidse. Some portion of these useful birds are 

 spread over every region of the world, and in almost 

 all localities. The section of the grouse to which 

 the muir-fowl of Britain and the ptarmigan belong, 

 occupy tlie wild heathy districts of the temperate 

 circle, and extend to the most barren and alpine moun- 

 tains, or the extremes of polar cold. The true 

 grouse, again, to which the European wood grouse 

 belongs, occupy the forest and bushy grounds, and ex- 

 tend almost as far. The partridges prefer open coun- 

 tries free from wood, and draw near to cultivation ; 

 but within the tropics there are one or two forms, 

 which, like the grouse, prefer the brush and wood, 

 where, on the branches, they are safer from the at- 

 tacks of the numerous tribes of reptiles which swarm 

 around them. The gangas, again, or, as they have 

 been named, the sand grouse, frequent the most bar- 

 ren districts in the world, the plains of India and the 

 trackless deserts of Africa and Arabia, far from the 



